A nonhydrostatic version of FVCOM : 1. Validation experiments

Author Posting. © American Geophysical Union, 2010. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 115 (2010): C11010, doi:10.1029/2009JC005525.The unstructured grid finite volume coastal ocean model (FVCOM) system has been expanded to include nonhydrostatic dynamics. This addition uses the factional step method with both split mode explicit and semi-implicit schemes. The unstructured grid finite volume method, combined with a correction of the final free surface from its intermediate value with inclusion of nonhydrostatic effects, efficiently reduces numerical damping and thus ensures second-order accuracy of the solutions with local/global volume conservation. Numerical experiments have been made to fully validate the nonhydrostatic FVCOM, including surface standing and solitary waves in idealized flat- and sloping-bottomed channels in homogeneous conditions, the density adjustment problem for lock exchange flow in a flat-bottomed channel, and two-layer internal solitary wave breaking on a sloping shelf. The model results agree well with the relevant analytical solutions and laboratory data. These validation experiments demonstrate that the nonhydrostatic FVCOM is capable of resolving complex nonhydrostatic dynamics in coastal and estuarine regions.This research was supported by NOAA g r a n t s DOC/NOAA/NA04NMF4720332 and DOC/NOAA/ NA05NMF4721131; US GLOBEC Northwest Atlantic/Georges Bank Program NSF grants OCE‐0234545, OCE‐0227679, OCE‐0606928, OCE‐0712903, OCE‐0732084, and OCE‐0726851; MIT sea grant 2006‐ RC‐103; and NOAA NERACOOS grant NA100558 for the UMASSD team and the Smith Chair in Coastal Oceanography and NOAA grant NA‐17RJ1223 for R.C. Beardsley. C. Chen’s contribution is also supported by Shanghai Ocean University International Cooperation Program (A‐2302‐10‐0003), the Program of Science and Technology Commission of Shanghai Municipality (09320503700), the Leading Academic Discipline Project of Shanghai Municipal Education Commission (Project J50702), and Zhi jiang Scholar and 111 project funds of the State Key Laboratory for Estuarine and Coastal Research, East China Normal University